libslang2-dev binary package in Ubuntu Bionic amd64

 S-Lang is a C programmer's library that includes routines for the rapid
 development of sophisticated, user friendly, multi-platform applications.
 .
 The S-Lang library includes the following:
  * Low level tty input routines for reading single characters at a time.
  * Keymap routines for defining keys and manipulating multiple keymaps.
  * A high-level key processing interface (SLkp) for
    handling function and arrow keys.
  * High level screen management routines for manipulating both
    monochrome and color terminals. These routines are very
    efficient. (SLsmg)
  * Low level terminal-independent routines for manipulating the display
    of a terminal. (SLtt)
  * Routines for reading single line input with line editing and recall
    capabilities. (SLrline)
  * Searching functions: both ordinary searches and regular expression
    searches. (SLsearch)
  * An embedded stack-based language interpreter with a C-like syntax.

Source package